Alpine951

I just put the 18 psi chips in my car. I can only get to 15 psi with the reliaboost running directly to the stock WG. My car is an 86 with the stock 26/6 turbo. I am thinking about upgrading the WG with the Guru since price is right its a bolt up. Are any of you having problems holding boost in the upper rpms and how much boost are you running?

streckfu's

Guru WG is a rebuilt stock unit and I beleive he uses a heavier spring. I don't own one, yet and cannot offer personal insight.

toddk911

I have a GURU wg and it holds any amount of boost I run. Boost comes on much faster then stock also, due to the GURU units spring not opening till about 10-12 psi, unlike stock which opens at like 4-5 psi and less for a worn out wastegate.

Alpine951

Streckfu,

thanks. i know what the Guru is, just wondering how its working. I know about the Lindsey and tials also.

Waterguy

The stock wastegate will hold over 20 psi at mid-range rpm (3500-4000 rpm) if the wastegate is disconnected completely from the banjo bolt. There are two different strengths of springs supplied with the Reliaboost, one that maxes out at 15-18 psi, and a stiffer one that allows you to set higher boost. You can probably just get a stiffer spring from your supplier.

This does not mean that there are no advantages to a better wastegate, but I am running 17 psi with a shimmed stock wastegate and Reliaboost plumbed drirect to the wastegate. I still have a tiny bit of adjustement range left on the Reliaboost.

Jake951

I have a Guru WG. With my old stock (shimmed) WG, I could develop lots of boost in the midrange but it would drop off to 12-13 psi by redline. With the Guru WG I can hold 15-15.5 psi to redline. However, since I have the 18 psi chips, I want to hold 18 psi to redline and the Guru WG doesn't quite make it. For this reason Danno is talking about a second generation Guru WG with an even stiffer spring. Meanwhile I just got a new Tial 38mm that I'm going to install soon and that I'm hoping will hold 18 psi to redline.

hosrom_951

With the tial, yours should hold

schnellfahrer

My car is in the shop right now having the Guru wastegate installed. I do hope it will be an improvement, because boost is late and drops quickly with the current wastegate. I'm kind of disappointed to hear Jake say that the Guru wastegate will not hold 18psi to redline. Maybe I should've bought a Tial instead. I was under the impression that the Guru wastegate was just as good as the Tial(in single port mode).
The car will hopefully be ready tomorrow or Friday.

Alpine951

I just put in the 18 psi chip from danno. He just emailed me about the Guru WG. I think i should inquire with him wether it will have the heavier spring.

Danno

I suspect Jake951's issue is his turbo. Most people with K26/8 turbos can hold 18psi to redline no problem. I have yet to see a K26/6 hold 18psi to redline, even with a Tial. Eclou and Jason_86_951 tried with both a GURU and Tial wastegate and they both got the same results, 18psi drops to about 15psi by redline.. I think the K26/6 just runs out of flow-capacity in the upper-RPMs.

The other thing is the mechanical nature of boost-control; it can't sense RPM and exhaust-pressure. An electronic controller can be programmed to close off the wastegate at high-RPMs to get a flatter boost-curve. WIth an AVC-R and a shimmed stock wastegate I was able to program in a rising boost-curve 15->16->17->18->19->20psi by redline. Also ended up bending the axle in the K26/6 turbo as well... Another guy in upstate New York recently tried wringing the most out of his K26/6 as well, I'm still waiting for the pictures of shrapnel...

ewainwright

I should chime in here. I second the Tial wastegate. Its not harder to replace than stock ( you'll have to remove the stock hanger and the Tial orientation is slightly different as oppose to the stock wastegate). Other than the occasional person who puts it on backwards (like I did), I haven't read any complaints about it.

I highly recommend getting the Tial from MySwiss. He promptly returns calls and emails when and if you have questions or problems. To me this is extremely important. You don't want to wait days even weeks to get items or answers to pressing questions answered while your car is sitting. ( I love driving mine even though I can use another car),

As with everything else on this car, you'll only want to do it once and with the Tial once its in you're finished. You'll find that you will really have to back out your reliboost (maybe get a weaker spring), your boost will come on much sooner and the Tial will hold boost to redline providing that your turbocharger is up to the challenge.

Alpine951

Danno,


should I expect to be able to see 18psi with a drop to about 15 psi with the Guru WG and a 26/6 turbo?

Jake951

It might be my turbo, but I won't really know until I get the Tial installed for comparison. However, I'm wondering what spring people are using in their Tial's when they can't hold the boost in the upper rpm's. I special-ordered my Tial with the 1.1 bar (16 psi) spring, which is not standard and costs a little bit extra. I'm hoping the stiffer spring will resist the exhaust pressure better so it doesn't open prematurely at high rpm's. If that doesn't work, then we'll know it's the turbo itself.

I should say, however, that with the Guru WG and stock K26/8 I made very close to 300 rwhp.

Danno

I think eclou had the 0.8-bar spring in his Tial as did Jason_86_951. You should get the stiffest spring possible that's just under your desired boost-levels. Then you can make the very last adjustment with the boost-controller. First test should be with the banjo-bolt direclty hooked up to the Tial. The resultant boost will be the native spring-pressure boost and it should match the 1.1-bar rating. If not, go up one spring-rate. It appears that the native boost you get is typically slightly lower than the spring-rating, so a 1.1-bar spring ends up at around 1.0-bar or so.

The spring I use in the GURU wastegate is effectively a 0.75-bar spring, or about twice as stiff as stock. But it's still not as stiff as I want. The next generation will have a 1.1-bar spring.

Alpine951

I have the single piece crossover on my car so a Tial would not be plug and play, right?